1. Field of the Invention
The present invention relates to a composite sheet and an absorbent article using the composite sheet.
2. Related Art
Composite sheets having a plurality of nonwoven fabrics laminated with adhesives or the like have been conventionally used in various applications and have been subjected to various types of processing in accordance with the intended uses or purposes. When used as absorbent articles, for example, the composite sheets are formed to improve the appearances and skin contact of the absorbent articles, and to expand and contract with the movements of the body or the like.
Furthermore, when used as absorbent articles, nonwoven fabrics having stretch properties are required to have strengths of which the absorbent articles endure use. Conversely, in order to produce absorbent articles with the practicality of use thereof maintained and at low costs, it is required that nonwoven fabrics having low basis weights and nonwoven fabrics having low strengths such as composite sheets are used.
Japanese Unexamined Patent Application Publication No. 2006-89907 discloses a method for subjecting a composite sheet to stretch processing two times in order to reduce damage to the composite sheet, in order to develop extensibility while reducing the damage to the sheet. However, in order to prevent fibers from being cut at the time of the stretch processing and prevent the sheet from being broken in this case, fibers having a high degree of elongation at break must be used. Furthermore, it is considered that a gap between the fibers is increased by extending and cutting the fibers in the stretching processing.
Here, when the gap between the fibers is great, adhesives used for bonding nonwoven fabrics to each other flow out. When the basis weight of the composite sheet is increased in order to prevent the adhesives from flowing out, the production cost is increased, and the practicality of use is adversely affected.